Thomas budworth sharp



T. B. SHARP.- APPARATUS FOR MANUFACTURING METAL TUBES.

(No Model.)

No. 600,681. Patented Man 15, 1898.

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THOMAS BUDWVORTH SHARP,

OF BIRMINGHAM, ENGLAND.

APPARATUS FOR MANUFACTURING METAL TUBES.

SPEOIFIGA TIGN forming part of Letters Patent No. 600,681, dated March15, 1898. Application filed October 191 1897. Serial No. 665,744. (Nomodel.) Patented in England August 6, 1897, No. 18,307.

To ctZZ whom it may concern.-

Be it known that I, THOMAS BUDwoRrH SHARP, engineer, a subject of theQueen of Great Britain, residing at County Chambers, Martineau street,Birmingham, in the county of WVarwick, England, have invented certainnew and useful Improvements in or Appertaining to the Manufacture ofSteel, Copper, or other Metal Tubes and in the Apparatus Employed in thesaid Manufacture, of which the following is a specification.

This invention has been patented in England under date of August 6,1897, No. 18,307.

My invention has for its object improvements in or appertaining to themanufacture of steel, copper, or other metal tubes and in. the apparatusemployed in the said manufacture, and is intended to produce metal tubesof variable thickness in a practically-finished condition and ready forworking into such forms as cycle, motor-car, and other frames, as wellas for boiler-tubes and many other purposes, in a readier, cheaper, andbetter manner than has hitherto been employed. I am quite aware that toa limited extent tubes thickened at the ends have been produced byjumping up; but such methods have been costly.

In order that my invention may be clearly understood and more easilycarried into practical effect, I have appended hereunto a sheet ofdrawings illustrating an example of my apparatus and the mode ofmanufacture or its application, which will enable others to apply theinvention to the various cases within practice.

Figure l is a sectional elevation of one of my casings or reducing-boxesA ready for. placing over the tube and mandrel before the operation ofreduction is commenced. Fig. 2 is an elevation of the left-hand end ofthe casing or reducing-box A. Fig. 3 is an elevation of the right-handend of the reducingbox A. Fig. 4. is a part section and part elevationof a tube T which has been reduced according to my invention and fromwhich the reducing-box A has been removed; but the tube is still on themandrel M. From this form it will be seen that the tube is held tightlyupon the mandrel and is prevented from turning, except with the mandrel,by the set-screw 7a, which is mounted in the holder K. This holder maybe permanently fixed upon any part of the mandrel M. There are manyother ways of holding the tube from turning upon the mandrel-such,forinstance, as a notch or notches in the end of the tube, taking into aprojection on the mandrel, or by a set-screw run through the tube, orthe tube may be allowed to bind itself by friction.

The casing or reducing-box A has an open end with a screw-thread a, intowhich the adjusting end E screws with its corresponding screw-thread eby means of the nut e solid with the end E, which also is formed with afacing-piece e at its inner end for. the purpose of operating trulyagainst the sliding cone 0, the opposite cone 0 being in the exampleshown stationary at the left end of the box, as shown upon the drawings.It will be seen that the cone 0 is first placed in the box, which isthen threaded over the tube T 011 the mandrel, when the balls 13 are putinto position. The back cone 0 is then placed in position and the end Eadjusted so as to bring the desired pressure upon the balls H, which isdue to the two inclined surfaces 0 and c ofthe cones, which are designedin this particular manner so as to best operate upon the tube to bereduced. The mandrel and tube are passed through the openings H in eachend of the box. Soap and water or other lubricant may be conveyed to thebox by the pipe P as required. The mandrel M, carrying its tube T andreducing-box A, is now placed in the lathe or machine, when the mandrel,with its tube, is rotated at a suitable speed, while the boxA is heldand traversed-over that portion of the tube it is required to reduce inthickness. The reduction may be done by traversing the box A once overthe tube or by doing so any number of times or with areciprocatingaction, the tightening of the balls upon the tube beingincreased by screwing up the end E upon the cone 0 or by otherequivalent adjust ment.

In preparing tubes for such purposes as the building of cycle-frames Itake a tube, say, for instance, eighteen inches long and one andone-eighth inches external diameter and, say, one thirty-second thick. Ithen arrange the travel of the box so as to reduce the thickness of thetube, say, fourteen inches of its middle length, leaving two inches ateach end not reduced When the box has been traversed once orreciprocated any desired number of times along the center portion, itwill be found that the length of the tube is increased and the thicknessdecreased until the desired thinness and length are reached. If the tubeis now examined, it will be found that the metal at the reduced portionis greatly consolidated and improved in texture, and we shall have athick-ended tube very light but very strong on account of the peculiartreatment it has received by the apparatus and process hereinbeforedescribed. Such a tube is suitable at its thick end for uniting tosockets or junctions either by brazing or by any other known means, andwhen so mounted in aframe the frame will be found much stronger and morereliable than frames made either from tubes of parallel thickness orfrom tubes staved up at the ends by the awkward means hitherto adoptedin an experimental and limited degree. If it is desired to have theshoulders of the tube inside at the ends, this may be accomplished byexternal pressure at the ends under dies or by a Ryder hammer or similartool.

Small friction-Wheels with rounded faces may be applied instead of theballs; but the action is not so good as the balls, which are free toadapt themselves in any direction to this peculiar work.

Though I have hitherto spoken of reducing tubes at the center only, theprocess and tool herein described are equally applicable to reducingtubes their entire length and are included in my invention. Tubes somanufactured are both stronger and lighter and better adapted for theirwork and more economical in every respect.

Having now particularly described and ascertained the nature of saidinvention and in What manner the same is to be performed, I declarewhat'I claim is In combination, the reducing-box A having one open side,the bearings O 0' located therein with a space between, the ballslocated betweenthe bearings, the adjusting-screw E threaded into theopen side of the reducingbox, the facing-surface 6 carried by theadjusting-screw and adapted to bear against the cone C and thelubricator-feed pipe communicating with the space between the cones,substantially as described.

In testimony that I claim the foregoing as my own I affix my name in thepresence of two witnesses. a

THOMAS BUDWORTH SHARP.

WVitnesses:

GEORGE LESTER, FREDERICK BUc LEY.

